OTTAWA -- In the past three days, the number of people in self-isolation with COVID-19 in Renfrew County has increased dramatically, according to figures from the Renfrew County and District Health Unit (RCDHU).

The RCDHU reported Tuesday that there are currently 32 people in self-isolation with COVID-19 in its region. Thirty of them are in the Pembroke area, and the other two are in and around Renfrew.

No one is in hospital.

This marks an increase of 18 cases compared to figures reported on Monday. All 18 of the new reported infections were in people in the Pembroke area.

On Sunday, the RCDHU said there were two people self-isolating with COVID-19. The region had zero active cases just one week ago.

On Friday, the RCDHU warned of spread amongst the members within a single-family household in a small Pembroke-area community after one person tested positive for COVID-19.

“This is a tightly knit community of over 30 families. We are taking all precautions to limit spread within the community and to prevent spread throughout Renfrew County and District,” Dr. Robert Cushman, Acting Medical Officer of Health said in a press release on Friday.

The RCDHU directed all families and persons impacted within the community to self-isolate until individual family status, exposure, and risks were assessed by the contact tracing team. The health unit tested about 70 people over the weekend.

Speaking to CTV News on Tuesday, Dr. Cushman said the affected community is a small one and health officials believe the virus may have first been spread by someone from outside.

“It’s not as if they had a big party or a wedding or anything like that. What we do think, too, is that it came in from southern Ontario, yet again,” he said. “While it’s quite a serious outbreak, no one has been very very sick to this point. Just a lot of symptoms and quite a lot of quick spread.”

Dr. Cushman added that he believes the virus won't spread too far beyond the community that has been affected, but the health unit will be monitoring the situation closely.

“We’re optimistic that this spread is going to be confined to the community, but we’ll have to wait the next few days to really get a handle on this,” he said.